The present invention relates generally to fasteners of the type having a flexible filament and more particularly to a novel such fastener and to a method of making said novel fastener.
Filamentary fasteners of the type commonly used to attach tags and the like to articles of commerce are well-known and widely used. Typically, such fasteners are unitary structures made of molded plastic. One such fastener, which is still in widespread use today, includes an elongated, flexible filament having a cross-bar disposed at a first end thereof and either a paddle or a second cross-bar disposed at a second end thereof. In use, the cross-bar disposed at the first end is typically inserted first through a tag and then through the desired article of commerce, with the paddle or second cross-bar not being inserted through the tag or article in order to retain the fastener and tag on the article. Typically, a plurality of the aforementioned fasteners are fabricated together as part of a fastener assembly, examples of which include fastener clips or continuously connected fastener stock. An example of a fastener clip is disclosed in U.S. Pat. No. 3,103,666, inventor Bone, which issued Sep. 17, 1963, and which is incorporated herein by reference. An example of continuously-connected fastener stock is disclosed in U.S. Pat. No. 4,121,487, inventor Bone, which issued Oct. 24, 1978, and which is incorporated herein by reference.
Typically, plastic fasteners of the types described above are fabricated as follows: First, molten plastic is injected into a mold having an impression resembling a fastener clip or continuously connected fastener stock. The molten plastic is then allowed to cool in the mold to the shape defined by the impression. Next, the molded plastic is removed from the mold, and the filamentary portions of the fasteners therein are stretched to a desired length and cross-sectional thickness.
One reason for molding the fastener assembly and then stretching the constituent filaments thereof to the desired final dimensions, as opposed to simply molding the fastener assembly with filaments having the desired final dimensions, is that it is very difficult to mold a filament so that it is as thin and as flexible as is often desired. Another reason is that the stretching of a filament typically alters the polymeric structure of the filament in a beneficial way, endowing the filament with certain physical properties (e.g., resistance against unwanted stretching and/or creeping) it otherwise would not enjoy. For these and other reasons, it has been much more desirable to mold a filamentary fastener so that the filament portion thereof is thicker and shorter than is ultimately desired and then to stretch the filament portion to the desired dimensions.
Typically, the above-described stretching of the filamentary portion of a fastener is performed with a specially-designed stretching machine, which grabs opposite ends of a fastener and pulls them apart in opposing directions. Unfortunately, such machines are often quite expensive, as is the automated equipment typically used to feed unstretched fasteners into said stretching machines.